Vertically adjustable two bar assembly

ABSTRACT

A tow bar assembly for towing one vehicle by another which enables the towed vehicle to be carried at a pre-determined or desired height above the ground, including a mounting plate having affixed thereto outwardly extending L-shaped brackets, each having a plurality of equally sized and spaced holes formed along a surface parallel to the surface of the mounting plate. A first wedge having a plurality of pins extending from it to engage selected ones of the holes in the brackets is provided together with a second wedge to maintain the interfitting engagement relationship of the pins in the holes, the second wedge jamming between the first wedge and the mounting plate. A tow bar, including a socket to receive a towing ball carried by a second vehicle, is mounted on the first wedge extending in the general direction of the pins, but is mounted at an angle with respect to a perpendicular to the surface of the first wedge of between about 5* and 25*, to enable the tow bar to be disposed substantially parallel to the ground when in connection with the towing ball, but enabling the towed vehicle to be carried at a desired height off the ground.

United States Patent Kendall 1 Sept. 19, 1972 r [54] VERTICALLYADJUSTABLE TWO BAR ASSEMBLY 72 inventor: Ray E. Kendall, Box

Alamogordo, N. Mex. 88310 [22] Filed: June 11, 1971 [21] Appl. No.:152,234

[56] References Cited UNITED STATES PATENTS 5/ 1958 Collins ..2l4/86 A3,269,751 8/1966 Whattoff ..280/490 R X 3,400,949 9/1968 Kendall..280/490 R FOREIGN PATENTS OR APPLICATIONS 926,224 4/1955 Germany..280/402 Primary Examiner-Leo Friaglia Attorney-Richard A. Bachard [57]ABSTRACT A tow bar assembly for towing one vehicle by another whichenables the towed vehicle to be carried at a predetermined or desiredheight above the ground, including a mounting plate having affixedthereto outwardly extending L-shaped brackets, each having a pluralityof equally sized and spaced holes formed along a surface parallel to thesurface of the mounting plate. A first wedge having a plurality of pinsextending from it to engage selected ones of the holes in the bracketsis provided together with a second wedge to maintain the interfittingengagement relationship of the pins in the holes, the second wedgejamming between the first wedge and the mounting plate. A tow bar,including a socket to receive a towing ball carried by a second vehicle,is mounted on the'first wedge extending in the general direction of thepins, but is mounted at an angle with respect to a perpendicular to thesurface of the first wedge of between about 5 and 25, to enable the towbar to be disposed substantially parallel to the ground when inconnection with thetowing ball, but enabling the towed vehicle to becarried at a desired height ofi the ground.

11 Claims, 4 Drawing Figures PAIENTEDsEP 19 I972 3.692.330

Roy E. Kendall QMWFEAM ATTORNEY INVEN TOR VERTICALLY ADJUSTABLE TWO BARASSEMBLY BACKGROUND OF THE INVENTION 1. Field of The Invention Thisinvention relates to improvements in vehicular towing apparatus, and,more particularly, to an improved tow bar for towing one vehicle byanother.

2. Description of The Prior Art Widely used today are towing apparatusesfor pulling or hauling one movable object by another; for example,hitchesand the like are widely available for pulling housetrailers orother rolling stock by car, truck, or other vehicle. Most of suchhitches include a ball or ball assembly which is generally attached tothe towing vehicle,'and a ball receptacle which frequently may compriseapart of a tow bar or tow bar assembly or the like, attached generallyto the towed vehicle or trailer.

Most of the towing apparatus used today for towing, as described, arenot of adjustable nature; however, becoming of increased use are trailerhitches or towing apparatus which are either vertically or horizontallyadjustable, to respectively allow the height at which the tow bar of thetowed vehicle may be adjusted, or allow the distance at which the towedvehicle is maintained from the towing vehicle. For example, the inventorherein has previously advanced a trailer hitch patented in U.S. Pat. No.3,400,949, which is vertically adjustable to facilitate up anddownadjustment, as aforesaid.

That hitch, which may be used in conjunction with the present invention,includes a vertical mounting plate which may be bolted or welded ontoone of the vehicles, preferably the towing truck. Two outstandingbrackets are provided, each presenting a surface parallel to the surfaceof the vertical mounting plate, each also having a plurality of holesformed in the parallel surface along its length. The ball portion of thehitch is so that no rotary motion will go through the gearbox and drivetrain of the towed truck as it is being hauled, thereby eliminating muchwear to the towed truck over the many towed miles. Thus, tow bars usedin the past were required to be so rigidly attached to the towed truckto enable it to be held off the ground, as described, and alsov to bestrong enough to haul the towed truck, in such elevated position, toallow it to be pulled as desired. It can be seen that permanently andrigidly attaching such tow bar to the towed truck can be cumbersome, andmay interfere with any subsequent towing process in which the towedtruck becomes again a towing truck upon reachin the destination, unlessthe rigidly attached tow bar is somehow removably fastened to thetowingtruck. In fact, it has been found so difficult and bothersome to attachtow bars of such fixed nature, that frequently the back end of the towedtruck is physically lifted over the rear of the towing truck and carriedover its fifth wheel.

BRIEF DESCRIPTION'OF THE INVENTION I In light of the above, therefore,it is an object of the invention to provide a tow bar which may beremovably attached to a towed vehicle, and which may be used to supportthe towed vehicle with selected ones of its wheels off the ground.

It is a further object of the invention to provide a tow bar which willnot interfere with subsequent towing processes if the towed vehicle islater used as a towing vehicle.

It is another object of the invention to provide a tow I bar usable inconjunction with vertically adjustable mounted upon a first wedge whichloosely interfits the I brackets and the vertical mounting plate. Thefirst wedge also includes a plurality of pins extending outwardly fromit in the same direction as the ball and which fit into any desired setof holes along the brackets, thereby allowing the ball assembly to beplaced at any desired vertical height. A second wedge is also providedwhich may be inserted between the first wedge ball assembly and thevertical plate to force the first wedge outwardly from the verticalplate to hold the pins of the ball assembly in mating relationship withthe holes of the brackets.

In the use and operation of this and similar hitches, a tow bar, usuallyattached to the object towed, including a ball receiving receptacle, isplaced in connection with the ball of the ball assembly. The tow bar isusually rigidly attached to the towed vehicle; although it may be boltedand often it is permanently welded thereto. Thus, in cases involvingtrailers and the like, any required vertical adjustment may beobtainable with such vertically adjustable hitch in connection with suchrigid tow bars.

However, frequently, especially when numbers of trailers are towed fromone location to another in a convoy, to return the trucks to theirstarting point, one truck is frequently used to tow another, for economyin gas, wear and tear, and for reaching the driver's convenience.Usually, the back end of the towed vehicle is raised to be towed withthe drive wheels off the ground hitches.

These and otherobjects, features, and advantages will become apparent tothose skilled in the art from the following detailed description, whenread in conjunction with the appended claims and accompanying drawing.

In accordance with the invention, in its broad aspect, a verticallyadjustable tow bar assembly is provided which includes a mounting platevertically mountable onto a vehicle. The mounting plate has affixed tothe side opposite that; upon which it is mounted, two brackets side byside to and outstanding from the mounting plate, each bracket presentinga surface parallel to the mounting plate and having formed therein aplurality of equally sized and spaced holes. A first wedge is alsoprovided which is tittable between the surfaces of the two brackets andthe mounting plate. Extending outwardly from the first wedge are aplurality of pins which are spaced and sized to be insertable intoselected ones of the plurality of holes in the mounting brackets. Tomaintain the pins in the selected holes, a second wedge is providedwhich is fittable between the first wedge and the mounting plate. A towbar for connection to a towing ball is' mounted on the firstwedge toextend therefrom in the same general direction as the direction of theplurality BRIEF DESCRIPTION OF THE DRAWING The invention is illustratedin the accompanying drawing, wherein:

FIG. 1 is a side view of a first vehicle towing a second, utilizing thetow bar assembly of the invention.

FIG. 2 is a perspective view, partially cut away, of the tow barassembly of the invention.

FIG. 3 is a perspective view of the tow bar mount used in conjunctionwith the tow bar assembly of FIG.

And FIG. 4 is a perspective of the position maintaining wedge used inconjunction with the tow bar assembly of FIG. 2.

Throughout the drawing and subsequent description, in referenceto thefigures of the drawing, it is understood that like reference numeralsindicate like parts. It should also be-understood various ones of theillustrated parts have been exaggerated for clarity and easeofdescription.

DETAILED DESCRIPTION OF THE INVENTION includes a mounting plate 31 ofgeneral wedge shape,

reduce the wear upon the drive chain, wheels, and

transmission which would occur if they were allowed to run on the groundduring towing. The particular height at which the wheels are carried maybe easily adjusted to any desired position, as below described.

The tow bar assembly-10 of the towed vehicle, the details of which areshown in FIG. 2, may be mounted upon Y the towed vehicle by mounting iton the rear frame, or as shown, upon supporting-braces 20 and 21 of thetowed truck 12 (shown in FIG, 1).,The tow bar assembly 10 is based upona vertical mounting plate 22, of steel or other strong material, whichserves to mount the tow bar assembly to the truck 12 and to support theother members of the tow bar assembly. Outstanding upon the mountingplate 22 are two L-shaped brackets '23 and 24, respectively, which maybe assembled of two flat pieces of metal welded into the required L-shape; alternatively, they may be cast as a single piece, as shown. Tostrengthen the bond made'at the junction between the L-shaped brackets23 and 24, several angle or brace pieces 25 may be provided upon whichadditional welds may be made to the mounting. Such brace pieces 25 mayconveniently be cast as a part of .the casting process in forming thebrackets 23 and24.

at various equally spaced intervals. These holes may thelarger end ofthe wedge being downwardly oriented. A plurality of pins 32 is providedupon the mounting plate 31, each of diameter slightly smaller than thediameter of the holes 28 in the outstanding surfaces 26 and 27, and ofapproximately the same spacing as the holes 28. Thepins 32 may be weldedonto the surface of the mounting plate 31, or they may be convenientlymade as a part of a casting process in the formation of the rigidmaterial of the mounting plate 31.

Also welded by welds 33 to the mounting plate 31 is a tow bar tongue 34which includes a ball receiving receptacle (downwardly disposed and notshown). The tow bar tongue 34 being of standard design widelycommercially available, and not described herein in detail, has, inaddition to the ball receiving receptacle, means for securing the towingball within the receiving receptacle, such means being denoted by thereference number 35.

The tow bar tongue 34, however, rather than being affixed to the towedvehicle, as usual, is welded to the mounting plate or wedge 31. Also,rather than being affixed at the normal perpendicular angle, it isdisposed at a downwardly extending angle of between 5 and 25, perhapsconveniently of 15 or more to facilitate the raising of the wheels ofthe towed vehicle off the ground, as mentioned above. The precise anglerequired will depend, of course, upon the type of vehicle towed; thefartherfrom the end of the vehicle its wheels are located, the largerthe angle required to raise them off the ground. It is desirable tochoose an angle for mounting the tow bar tongue such that when the towedvehicle is carried at the desired height above the ground, the tow bartongue itself is substantially parallel to the ground. Thus, with thetow bar tongue so disposed, the towing ball will be free to move in anylateral rotational position within the socket of the tow bar tonguewithout binding or interferring with turning operations with respect tothe towed and towing vehicles. The tow bar mount, thus described, isthen carrie upon the mounting plate 22 between it and the outstandingsurfaces 26 and 27, and is vertically adjustable by locating the pins 32in any desired ones of the holes To secure the mounting plate 31 in thechosen height position, a wedge 40, shown in FIG. 4, is provided. Thewedge 40, opposite from mounting plate 31, has its larger end upwardlyoriented, as illustrated, and is of thickness such that the totalthickness of the wedge 40 juxtaposed in alignment with the mountingplate 31 is slightly larger than the distance between the mounting plate22 and the outstanding surfaces 2 6 and 27 to allow it to jam againstand hold the mounting plate 31 with the pins 32 in engagement with theholes 28. To ease in insertion of the wedge plate 40, a handle 41 isprovided on its upward end.

The mounting plate 31 being similar to the plate previously proposed bythe inventor, above-described to carry a towing ball, is compatible withthe present invention, and may easily be transformed from a towingvehicle structure to a towed vehicle structure merely by substitutingfor the ball mount the tow bar tongue, mounted, of course, squarely upona similar mounting plate 31. Thus, the structure of the invention may beused in conjunction with a ball assembly to tote or haul a trailer orthe like to a desired location. Then, by substituting the tow barassembly for the ball assembly, the truck may be reversed and towed tothe original or other destination.

Although the invention has been described and illustrated with a certaindegree of particularity, it is understood that the present disclosurehas been made only by way of example, and that numerous changes in thedetails of construction and the combination and arrangement of parts maybe resorted to without departing from the spirit and scope of theinvention as hereinafter claimed.

What is claimed is:

1. A vertically adjustable tow bar assembly, comprisa mounting platevertically mountable on a vehicle,

two brackets affixed side by side to and outstanding from said mountingplate, each presenting a surface parallel to said mounting plate, eachof said presented surfaces having therein a plurality of equally sizedand spaced holes,

a first wedge fittable between said presented surfaces and said mountingplate,

a plurality of pins extending outwardly from said first wedge, saidplurality of pins being spaced and sized to be insertable into selectedones of said plurality of holes,

a second wedge fittable between said first wedge and said mounting plateto force said plurality of pins into said selected holes, and

a tow bar mounted on said first wedge to extend therefrom in the samegeneral direction as the direction of said plurality of pins beingdisposed at a downward angle to enable the vehicle on which said tow barassembly is mounted to be carried at a predetermined height above theground with the LII 4. The tow bar assembly of claim 2 wherein said towbar is welded to said first wedge.

5. The tow bar assembly of claim 4 wherein said tow bar comprises meansfor receiving a towing ball and means for securing said towing ball insaid receiving means.

6. A tow bar wedge assembly for use in a vertically adjustable hitch ofthe type wherein a first wedge having first enga ement means is heldbetween a mounting plate and rackets outstanding therefrom having secondengagement means, with said first and second engagement means engaged,by a second wedge interfitting said first wedge and said mounting plate,comprising:

a wedge having front and back faces,

a plurality of protrusions extending from said wedge to form said firstengagement means,

and a tow bar mounted on the front, face of said wedge at a downwardlyextending angle from the perpendicular to the front face.

7. The tow bar wedge assembly of claim 6 wherein said plurality ofprotrusions is a plurality of pins extending from the front face of saidwedge.

8. The tow bar wedge assembly of claim 7 wherein said downwardlyextending angle is between approximately 5 and 25.

9. The tow bar assembly of claim 7 wherein said downwardly extendingangle is approximately 15.

10. A vertically adjustable tow bar assembly comprising: i

a plate mountable on the rear of a truck;

two L-shaped brackets attached to said plate in spaced-apartrelationship disposed parallel to each other to define a void area overwhich portions of said L-shaped brackets overhand, said overhangingportions having a plurality of equally sized and spaced holes therein;

a first wedge loosely fittable in said void area,

a plurality of pins spaced upon said first wedge and sized to interfitselected ones of the holes in said overhanging portions;

a second wedge insertable between said first wedge and said plate tomaintain the interfitting relationship of said plurality of pins and thesaid selected ones of the holes in said overhanging portions, and

means for receiving a towing ball, being mounted on said first wedgeextending in the general direction of said plurality of pins at adownward angle of between approximately 5 and 25 from the normal to thesurface of said first wedge whereby said means is disposed approximatelyparallel to the ground when in connection with the towing ball.

11. The adjustable tow bar of claim 10 wherein said means for receivinga towing ball is a tow bar and further comprising means in said tow barfor securing said towing ball.

1. A vertically adjustable tow bar aSsembly, comprising: a mountingplate vertically mountable on a vehicle, two brackets affixed side byside to and outstanding from said mounting plate, each presenting asurface parallel to said mounting plate, each of said presented surfaceshaving therein a plurality of equally sized and spaced holes, a firstwedge fittable between said presented surfaces and said mounting plate,a plurality of pins extending outwardly from said first wedge, saidplurality of pins being spaced and sized to be insertable into selectedones of said plurality of holes, a second wedge fittable between saidfirst wedge and said mounting plate to force said plurality of pins intosaid selected holes, and a tow bar mounted on said first wedge to extendtherefrom in the same general direction as the direction of saidplurality of pins being disposed at a downward angle to enable thevehicle on which said tow bar assembly is mounted to be carried at apredetermined height above the ground with the base of said tow barsubstantially parallel to the ground.
 2. The tow bar assembly of claim 1wherein said downward angle is between approximately 5* and 25*.
 3. Thetow bar assembly of claim 1 wherein said downward angle is approximately15*.
 4. The tow bar assembly of claim 2 wherein said tow bar is weldedto said first wedge.
 5. The tow bar assembly of claim 4 wherein said towbar comprises means for receiving a towing ball and means for securingsaid towing ball in said receiving means.
 6. A tow bar wedge assemblyfor use in a vertically adjustable hitch of the type wherein a firstwedge having first engagement means is held between a mounting plate andbrackets outstanding therefrom having second engagement means, with saidfirst and second engagement means engaged, by a second wedgeinterfitting said first wedge and said mounting plate, comprising: awedge having front and back faces, a plurality of protrusions extendingfrom said wedge to form said first engagement means, and a tow barmounted on the front face of said wedge at a downwardly extending anglefrom the perpendicular to the front face.
 7. The tow bar wedge assemblyof claim 6 wherein said plurality of protrusions is a plurality of pinsextending from the front face of said wedge.
 8. The tow bar wedgeassembly of claim 7 wherein said downwardly extending angle is betweenapproximately 5* and 25*.
 9. The tow bar assembly of claim 7 whereinsaid downwardly extending angle is approximately 15*.
 10. A verticallyadjustable tow bar assembly comprising: a plate mountable on the rear ofa truck; two L-shaped brackets attached to said plate in spaced-apartrelationship disposed parallel to each other to define a void area overwhich portions of said L-shaped brackets overhand, said overhangingportions having a plurality of equally sized and spaced holes therein; afirst wedge loosely fittable in said void area, a plurality of pinsspaced upon said first wedge and sized to interfit selected ones of theholes in said overhanging portions; a second wedge insertable betweensaid first wedge and said plate to maintain the interfittingrelationship of said plurality of pins and the said selected ones of theholes in said overhanging portions, and means for receiving a towingball, being mounted on said first wedge extending in the generaldirection of said plurality of pins at a downward angle of betweenapproximately 5* and 25* from the normal to the surface of said firstwedge whereby said means is disposed approximately parallel to theground when in connection with the towing ball.
 11. The adjustable towbar of claim 10 wherein said means for receiving a towing ball is a towbar and further comprising means in said tow bar for securing saidtowing ball.